PIG discharge with two pressure gradients of Ar gas introduced from the cathode region is investigated. The first pressure gradient is maintained by two intermediate electrodes inserted between the cathode region (40 Pa) and the anode region (1.3 Pa), which protects the cathode from bombardment of positive Ar ions and reactive gases in plasma processes. The second pressure gradient is maintained by an anode ring inserted btween the anode region and the main vacuum chamber (4×10
-2 Pa), which contributes to the increase of the pressure of Ar gas in the anode region and to producing a high-density plasma by full ionization. The PIG discharge with a magnetic field of about 500 gauss is fired under a discharge current of 100 A and voltage of 70 V. Then, the discharge plasma flow with a high-density (10
14/cc) enters the main chamber through a central aperture of the anode ring and is transformed into a sheet plasma flow by a pair of permanent magnets and a weak magnetic field of about 10 gauss in the main chamber. The sheet plasma density and electron temperature are about 3×10
11/cc and 13 eV over a surface area of 80cm×60cm and a thickness of 15 cm, which are very useful for development of plasma processes.
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